SUMMARY: fsck checks filesystems twice

The "problem":
If fsck finds a problem in /usr, it doesn't exit immediately after
repairing the problem, rather it checks all of the other filesystems.
Consequently, all of the filesystems get checked twice; ie, again
during the reboot after repairing /usr. (Yes, this is a rare;
for example, autoreboot due to a power glitch.)

From: simon@Aus.Sun.COM (Simon Woodhead - Technical Consultant)
4.1.2 includes the QuickCheck utility which keeps an eye on the
file system state *all the time* (well, between /usr/etc/updates),
and sets a flag for each filesystem indicating that it is stable.

From: Mike Raffety <miker@sbcoc.com>
However, how often does fsck ever need to fix
anything in /usr? We generally make the mount read-only, so fsck
doesn't even look at it, and things go even faster. Even if it were
read-write, I'd say that the problem is awfully rare (once in a hundred
boots, since 99 are clean halts or shutdowns).

From: mdl@cypress.com (J. Matt Landrum)
I think it's probably a mistake on sun's part.
As and aside...
If you aren't going to 4.1.2 soon, I recommend you get
quick check (from Sun - $500 and worth every penney).
One of my 4/280s with 4 892 disks takes 10 minutes
for a full fsck (it used to take 45+). I think
this will be bundled in future O/S releases.